1. Field of the Invention
This invention relates to a drivetrain for an automotive vehicle, more particularly to a drivetrain having an axle differential mechanism and a speed reduction gearset located at each driven wheel.
2. Description of the Prior Art
Various drivelines having a speed reduction gearset at each driven wheel of a motor vehicle have been employed for different purposes. For example, U.S. Pat. No. 4,860,843 describes a driveline for a tractor, in which the rear wheels are supported on a U-shaped frame having legs extending rearward. Power developed by an engine is transferred through a differential mechanism located forward of the axle shafts from a differential mechanism through right-hand and left-hand chain drive mechanisms rearward to the vicinity of the driven wheels. The chain drive mechanisms each drive a simple speed reduction gearset whose output is driveably connected to the corresponding axle shaft. This arrangement of the power flow provides a free space between the legs of the U-shaped frame between the rear wheels so that auxiliary units can be readily coupled to the frame of the tractor.
U.S. Pat. No. 4,315,556 describes a hub reduction gear unit located in the hub of the vehicle, the gear unit being in the form an epicyclic gear train.
U.S. Pat. No. 4,249,631 describes a drive axle for steerable wheels, the axle pivotally mounted on the frame of the motor vehicle having two drive shafts angled mutually in a V-shaped configuration opening downward and rearward to increase the distance between the axle housing and the ground.
In another application of a speed reduction gearset located at the wheel hub, the gearset is used to raise the distance between the ground level and the frame of the motor vehicle in order to facilitate ground clearance for off-road use of the vehicle.